 var $ = function (id) {
        return "string" == typeof id ? document.getElementById(id) : id;
    }
    var Bind = function (object, fun) {
        return function () {
            return fun.apply(object, arguments);
        }
    }
    function AutoComplete(obj, autoObj, arr) {
        this.obj = $(obj); //输入框
        this.autoObj = $(autoObj);//DIV的根节点
        this.value_arr = arr; //不要包含重复值
        this.index = -1; //当前选中的DIV的索引
        this.search_value = ""; //保存当前搜索的字符
    }
    AutoComplete.prototype = {
        //初始化DIV的位置
        init: function () {
            this.autoObj.style.left = this.obj.offsetLeft + "px";
            this.autoObj.style.top = this.obj.offsetTop + this.obj.offsetHeight + "px";
            this.autoObj.style.width = this.obj.offsetWidth - 2 + "px";//减去边框的长度2px
        },
        //删除自动完成需要的所有DIV
        deleteDIV: function () {
            while (this.autoObj.hasChildNodes()) {
                this.autoObj.removeChild(this.autoObj.firstChild);
            }
            this.autoObj.className = "auto_hidden";
        },
        //设置值
        setValue: function (_this) {
            return function () {
                _this.obj.value = this.seq;
                _this.autoObj.className = "auto_hidden";
            }
        },
        //模拟鼠标移动至DIV时，DIV高亮
        autoOnmouseover: function (_this, _div_index) {
            return function () {
                _this.index = _div_index;
                var length = _this.autoObj.children.length;
                for (var j = 0; j < length; j++) {
                    if (j != _this.index) {
                        _this.autoObj.childNodes[j].className = 'auto_onmouseout';
                    } else {
                        _this.autoObj.childNodes[j].className = 'auto_onmouseover';
                    }
                }
            }
        },
        //更改classname
        changeClassname: function (length) {
            for (var i = 0; i < length; i++) {
                if (i != this.index) {
                    this.autoObj.childNodes[i].className = 'auto_onmouseout';
                } else {
                    this.autoObj.childNodes[i].className = 'auto_onmouseover';
                    this.obj.value = this.autoObj.childNodes[i].seq;
                }
            }
        },
 
        //响应键盘
        pressKey: function (event) {
            var length = this.autoObj.children.length;
            //光标键"↓"
            if (event.keyCode == 40) {
                ++this.index;
                if (this.index > length) {
                    this.index = 0;
                } else if (this.index == length) {
                    this.obj.value = this.search_value;
                }
                this.changeClassname(length);
            }
                //光标键"↑"
            else if (event.keyCode == 38) {
                this.index--;
                if (this.index < -1) {
                    this.index = length - 1;
                } else if (this.index == -1) {
                    this.obj.value = this.search_value;
                }
                this.changeClassname(length);
            }
                //回车键
            else if (event.keyCode == 13) {
                this.autoObj.className = "auto_hidden";
                this.index = -1;
            } else {
                this.index = -1;
            }
        },
        //程序入口
        start: function (event) {
            if (event.keyCode != 13 && event.keyCode != 38 && event.keyCode != 40) {
                this.init();
                this.deleteDIV();
                this.search_value = this.obj.value;
                var valueArr = this.value_arr;
                valueArr.sort();
                if (this.obj.value.replace(/(^\s*)|(\s*$)/g, '') == "") { return; }//值为空，退出
                try { var reg = new RegExp("(" + this.obj.value + ")", "i"); }
                catch (e) { return; }
                var div_index = 0;//记录创建的DIV的索引
                for (var i = 0; i < valueArr.length; i++) {
                    if (reg.test(valueArr[i])) {
                        var div = document.createElement("div");
                        div.className = "auto_onmouseout";
                        div.seq = valueArr[i];
                        div.onclick = this.setValue(this);
                        div.onmouseover = this.autoOnmouseover(this, div_index);
                        div.innerHTML = valueArr[i].replace(reg, "<strong>$1</strong>");//搜索到的字符粗体显示
                        this.autoObj.appendChild(div);
                        this.autoObj.className = "auto_show";
                        div_index++;
                    }
                }
            }
            this.pressKey(event);
            window.onresize = Bind(this, function () { this.init(); });
        }
    }